Re: Export of the integer value in fixedpoint toolbox

[David Bateman]

Jan Trmal wrote:

>Hello,
>I'm just wondering, if it is possible somehow gain the acces to the integer 
>representation of the fixed point number. It could be used for example during 
>the process of calculation of coefficient of some filter or so, for further 
>implementation in HW. I would highly appreciate it. Nowadays, I have to 
>perform all my calculations using IT++ or using matlab. 
>I'm aware, that can be realized just using expresion like a.x * (2^a.dec), but 
>I would have to take care about the sign of the variable, so it would be much 
>more comfortable to write for example x.i = 7; x = x* y; disp(x.i)
>I could try, if someone guides me, (I guess it could be relatively easy), but 
>I'm quite unexperienced in octave-C++ programming. 
>Thanks in advance for any comment on this.
>Yenda
>
>  
>
Yenda,

The code for this is available to an oct-file in the getnumber method.
However it is not exposed to the script files. Adding appropriate code to

octave_base_fixed<ST>::dotref (const octave_value_list& idx)

to allow access to the integer representation should be all that is
needed. Something like

#define __FIXED_INT_VALUE_STR "i"  // added to fixed-def.h

<snip>

  else if (nm == __FIXED_INT_VALUE_STR)
    retval(0) = octave_value (scalar.getnumber());

and similar code to octave_base_fixed_matrix<MT>::dotref (const
octave_value_list& idx). The GET_FIXED_PROP(getnumber) would also need
to be added to fixedComplex.h, etc. For cleanness the new case should be
treated in the subsasgn functions as well.

I'm sorry I really don't have time to add this feature now, but would
commit a patch if you are willing to work on one and test it.

D.

-- 
David Bateman                                address@hidden
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